Tick Infestation and Tick-borne Diseases Infection of Dogs in Okinawa Island

Rhipicephalus sanguineus and Haemaphysalis longicornis ticks were detected from 58 (57.4%) and 2, respectively, of 101 dogs examined in Okinawa Island. Of 170 sera 25 (14.7%) and 3 were positive for antibodies to Ehrlichia canis and Hepatozoon canis, respectively, while 16 (9.4%) had antibody to Babesia gibsoni. On the smear samples of peripheral blood from 164 dogs, there were no infected cells with E. canis or H. canis, while 8 of 164 (4.9%) were shown to be infected with Babesia spp. Microfilarias were seen on the peripheral blood from 35 of 164 (21.3%) dogs, and all of them were morphologically identified as those of mosquito-borne Dirofilaria immitis but not of tick-borne Dipetalonema spp.